What is the physical property of a circuit that ensures it opposes a change in voltage?

The property that opposes a change in voltage within a circuit is capacitance. Capacitors store electrical energy in an electric field when a voltage is applied across them, and they release that energy when the voltage changes. This ability to store energy allows capacitors to resist changes in voltage, effectively smoothing out fluctuations and helping to maintain a stable voltage within the circuit.

When a voltage across a capacitor changes, the capacitor reacts by charging or discharging in response to that change. This characteristic is essential in applications such as filtering, timing circuits, and energy storage, as it provides a means of managing voltage levels even when there are disturbances in the electrical system.

Inductance, on the other hand, is primarily responsible for opposing changes in current in a circuit rather than voltage. Resistance is the property that dissipates electrical energy, which does not provide the same opposing function to changes in voltage as capacitance does. Conductance measures how easily electricity flows through a material and is the inverse of resistance, thus not applicable for opposing changes in voltage either.